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Friday, February 22, 2019

zVex Machine

Happy Fuzz Friday! Not sure how I haven't laid this one out before. Think of it like a mashup of a SHO and Tim Escobedo's Tripple Fuzz, and then repeated. Here's the schematic for reference. This one was drawn up based on an early 2000s model and the input SHO section I've modified to the newer version with a single 9.1v zener to protect the MOSFET instead of 2, 1N4148s in the layout below. I also added a pulldown resistor at the output (cuz I couldn't make it fit at the input lol). The 2 clipping diodes aren't known, other than they are large blue glass diodes with the markings "BKC" written on them, so socket and experiment.



11 comments:

  1. The diodes in position D2-D3 might be 1N277 Germanium diodes military version - as they were coated with blue to mark them as a mil spec-compliant component. So my guess is that a germanium diode should do :)

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  2. BKC blue diodes:
    https://www.ebay.co.uk/itm/1N5187-SWITCHING-DIODE-200V-3A-2-PER-LOT-/152422592117

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  3. 1N34A (blue body marked BKC) Voltage: 45Vrm peak. Current: 50mA

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    1. Agreed. Vex commented about this layout:
      "a pair of back-to-back germanium diodes to the output in order to fuzz out the taller direct guitar waves and make them about the same size as the crossover distortion triangles."

      I'll be using some Russian D9E diodes and call it good.

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  4. verified.Used soviet germanium D9, I had not enough volume. I have changed 22k from collectors Q2,Q3 to earth, from 22k to 100 k & got good excite!

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  5. & yet, if you like experiments, try change both 5k1 resistors up to 20-40k

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  6. This is video, How i make my pedals https://www.youtube.com/watch?v=WvfBaE81d-A&feature=youtu.be

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  7. Just built this today, works good, thanks for the layout

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  8. I built this. It works except I’m getting an oscillation. I believe it’s from the zener diode. Is there anything I can do to fix that?

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  9. I built this. It works except I’m getting an oscillation. I believe it’s from the zener diode. Is there anything I can do to fix that?

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  10. I built this. It works except I’m getting an oscillation. I believe it’s from the zener diode. Is there anything I can do to fix that?

    ReplyDelete